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LiteSpeed Cache vulnerabilities
LiteSpeed Cache has 11 known vulnerabilities in this database. The most recent published record is dated 19 Sep 2026.
- Known vulnerabilities
- 11
- Active installs
- 7m+
- Latest version
- 7.9.1
- Last updated
- 1 Sep 2026
- Most recent
- 19 Sep 2026
Find it in your WordPress dashboard under Plugins. Severity is based on the CVSS score published with the CVE where one is available.
| Vulnerability | Severity | Affected | Fix | Published |
|---|---|---|---|---|
| Cross-site scripting (XSS) CVE-2026-76579 | Medium 4.7 | Up to 7.9 | Fixed in a later version (latest 7.9.1) | 19 Sep 2026 |
| Cross-site scripting (XSS) CVE-2026-3129 | Medium 6.4 | Up to 7.7 | Fixed in a later version (latest 7.9.1) | 28 Aug 2026 |
| Cross-site scripting (XSS) CVE-2026-18978 | High 7.2 | Up to 7.8.1 | Fixed in a later version (latest 7.9.1) | 28 Aug 2026 |
| Cross-site scripting (XSS) CVE-2026-3375 | High 7.2 | Up to 7.7 | Fixed in a later version (latest 7.9.1) | 27 May 2026 |
| Cross-site scripting (XSS) CVE-2025-12450 | Medium 6.1 | Up to 7.5.0.1 | Fixed in a later version (latest 7.9.1) | 29 Oct 2025 |
| Cross-site scripting (XSS) CVE-2024-9169 | Medium 5.5 | Before 6.5 | Fixed in 6.5 | 25 Sep 2024 |
| Cross-site request forgery (CSRF) CVE-2024-3246 | Medium 6.1 | Before 6.3 | Fixed in 6.3 | 24 Jul 2024 |
| Cross-site scripting (XSS) CVE-2023-4372 | Medium 6.4 | Up to 5.6 | Fixed in a later version (latest 7.9.1) | 11 Jan 2024 |
| Cross-site scripting (XSS) CVE-2021-24963 | Medium 4.8 | Before 4.4.4 | Fixed in 4.4.4 | 3 Jan 2022 |
| Cross-site scripting (XSS) CVE-2021-24964 | Medium 6.1 | Before 4.4.4 | Fixed in 4.4.4 | 3 Jan 2022 |
| Cross-site scripting (XSS) CVE-2020-29172 | Medium 6.1 | Before 3.6.1 | Fixed in 3.6.1 | 26 Dec 2020 |
Read the published descriptions
- CVE-2026-76579, 19 Sep 2026
- The LiteSpeed Cache plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'esi' parameter in all versions up to, and including, 7.9 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link. Exploitation requires that the attacker supply a validly signed 'esi' value in the GET query string while submitting a separate attacker-controlled 'esi' payload as a POST body field, relying on PHP's default $_REQUEST merge order to have the POST value take precedence at the point of execution. CVE record
- CVE-2026-3129, 28 Aug 2026
- The LiteSpeed Cache plugin for WordPress is vulnerable to Stored Cross-Site Scripting via crafted `<img>` tag attributes in all versions up to, and including, 7.7. This is due to a flawed regular expression that is used to strip `width` and `height` attributes from images when the "Lazy Load Images" and "Add Missing Sizes" features are enabled. This makes it possible for authenticated attackers, with Author-level access and above, to inject arbitrary web scripts in pages that execute whenever a user accesses an injected page. CVE record
- CVE-2026-18978, 28 Aug 2026
- The LiteSpeed Cache plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Comment Content in all versions up to, and including, 7.8.1 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. A comment payload crafted exclusively from decimal numeric character references (e.g. ", <, >) placed inside an allowed element such as <code> bypasses WordPress's wp_kses sanitization, as kses does not treat a data-settings="..." substring within text content as an HTML attribute, allowing the malicious payload to reach the vulnerable function. For this to be exploitable, the site must allow users with previously approved comments to write new comments, and the require_name_email setting must be disabled. CVE record
- CVE-2026-3375, 27 May 2026
- The LiteSpeed Cache plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the /wp-json/litespeed/v1/notify_ccss and /wp-json/litespeed/v1/notify_ucss REST API endpoints in all versions up to, and including, 7.7. These endpoints accept CSS content from QUIC.cloud callback notifications and store it to disk without sanitization. The stored content is later rendered inline frontend page loads without output escaping. The access control protecting these endpoints is IP-based validation that can potentially be bypassed when the WordPress site is deployed behind a reverse proxy, load balancer, or CDN with certain configurations. This makes it possible for unauthenticated attackers, under certain conditions, to inject arbitrary JavaScript into CCSS/UCSS content. CVE record
- CVE-2025-12450, 29 Oct 2025
- The LiteSpeed Cache plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via URLs in all versions up to, and including, 7.5.0.1 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link. CVE record
- CVE-2024-9169, 25 Sep 2024
- The LiteSpeed Cache plugin for WordPress is vulnerable to Stored Cross-Site Scripting via plugin debug settings in all versions up to, and including, 6.4.1 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level permissions and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled. CVE record
- CVE-2024-3246, 24 Jul 2024
- The LiteSpeed Cache plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 6.2.0.1. This is due to missing or incorrect nonce validation. This makes it possible for unauthenticated attackers to update the token setting and inject malicious JavaScript via a forged request granted they can trick a site administrator into performing an action such as clicking on a link. CVE record
- CVE-2023-4372, 11 Jan 2024
- The LiteSpeed Cache plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'esi' shortcode in versions up to, and including, 5.6 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers with contributor-level and above permissions to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. CVE record
- CVE-2021-24963, 3 Jan 2022
- The LiteSpeed Cache WordPress plugin before 4.4.4 does not escape the qc_res parameter before outputting it back in the JS code of an admin page, leading to a Reflected Cross-Site Scripting CVE record
- CVE-2021-24964, 3 Jan 2022
- The LiteSpeed Cache WordPress plugin before 4.4.4 does not properly verify that requests are coming from QUIC.cloud servers, allowing attackers to make requests to certain endpoints by using a specific X-Forwarded-For header value. In addition, one of the endpoint could be used to set CSS code if a setting is enabled, which will then be output in some pages without being sanitised and escaped. Combining those two issues, an unauthenticated attacker could put Cross-Site Scripting payloads in pages visited by users. CVE record
- CVE-2020-29172, 26 Dec 2020
- A cross-site scripting (XSS) vulnerability in the LiteSpeed Cache plugin before 3.6.1 for WordPress can be exploited via the Server IP setting. CVE record
What to do if you run LiteSpeed Cache
If you run LiteSpeed Cache, open WordPress and check the installed version in Plugins. Compare it with the affected versions in the vulnerability record. If a fixed version is available, take a current backup and update to that version or the latest supported release.
If no fixed version exists, consider disabling and removing the plugin or replacing it with a maintained alternative. After dealing with the affected software, check administrator users, unexpected file changes, redirects, unfamiliar pages and security logs for signs that the site may already have been altered.
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